Message #26694

[Bianca]

The Tetrabiblos was enormously influential in its time, and for centuries after.

Other astrologers, such as Hephaestion of Thebes, Paul of Alexandria and Julius Firmicus, used it, and saw it as a seminal work. Even today it is read by astrologers, not merely because some of its precepts are part of astrological heritage, but because it offers cogent arguments to support its theory.

For instance, Ptolemy grasped the nettle of the Precession of the Equinoxes, pointing out that 'the beginnings of the signs are to be taken from the equinoctial and tropical points. This rule is not only stated very clearly by writers on the subject, but it is also evident by the demonstrations constantly afforded, that their natures, influences and familiarities have no other origin than from the tropics and equinoxes ...' In other words, it is the 30 degree section of the ecliptic within which planets may be placed that matters, and not the fact that certain constellations may or may not be behind them.

Yet that hoary old argument is still raked up, despite the fact that Ptolemy settled it firmly two thousand years ago.